In percutaneous transluminal coronary angioplasty (PTCA) procedures to treat a stenosis in an artery, a guiding catheter is advanced until the distal tip of the guiding catheter is seated in the ostium of a body lumen, such as a coronary artery. A guide wire, positioned within an inner lumen of a dilatation catheter, is first advanced out of the distal end of the guiding catheter into the patient's coronary artery until the distal end of the guide wire crosses a lesion to be dilated. Then the dilatation catheter having an inflatable balloon on the distal portion thereof is advanced into the patient's cardiovascular system, over the previously introduced guide wire, until the balloon of the dilatation catheter is properly positioned across the lesion. Once properly positioned, the dilatation balloon is inflated with liquid one or more times to a predetermined size at relatively high pressures (e.g. greater than 6 atmospheres) so that the stenosis in a blood vessel is compressed against the arterial wall and the wall expanded to open up the passageway. Generally, the inflated diameter of the balloon is approximately the same diameter as the native diameter of the body lumen being dilated so as to complete the dilatation but not overexpand the artery wall. Finally, the balloon is deflated, blood flow resumes through the dilated artery, and the dilatation catheter can be removed therefrom.
After angioplasty procedures, restenosis may form in the artery at the original stenotic site, necessitating either another angioplasty procedure, or some other method of repairing or strengthening the dilated area. To reduce the restenosis rate and to strengthen the dilated area, physicians frequently implant an intravascular prosthesis, generally called a stent, inside the artery at the site of the lesion. Stents may also be used to repair vessels having an intimal flap or dissection or to generally strengthen a weakened section of a vessel. Stents are usually delivered to a desired location within a coronary artery in a contracted condition on a balloon of a catheter which is similar in many respects to a balloon angioplasty catheter, and expanded to a larger diameter by expansion of the balloon. The balloon is deflated to remove the catheter and the stent left in place within the artery at the site of the dilated lesion.
In the design of catheter balloons, the balloon shape and length must be tailored to provide optimal performance for a particular application, whether it be angioplasty, stent delivery, or other application. In many cases, it may be desired to produce balloons of different lengths but with similar diameters and tapers. Balloons adapted to a particular purpose may be produced in several lengths to accommodate different patient characteristics and physician preferences.
The manufacture of catheter balloons is a delicate and expensive undertaking. Typically, molds of the desired shape and size are created for each balloon design to be manufactured. Such molds are difficult and expensive to produce. In addition, each time it is desired to manufacture a different balloon catheter, time and labor must be expended in changing molds. Accordingly, there is need in the art for catheter balloon molds adaptable for use in the manufacture of multiple balloon designs so as to reduce the cost and improve the efficiency of processes for the manufacturing of inflatable members, such as balloon catheters.